This paper aims at increasing the accuracy of the signal acquisition system and decreasing the non-linear error of the A/D conversion. A multi-channel high-accuracy signal acquisition card based on PCI bus is designed and a Windows Driver Model (WDM) driver for multiple cards with same configuration is described. The local bus of the card is controlled by the temporal logic of a programmable FPGA, which manages a high-speed A/D converter with 16-bit accuracy and two 8M-bit SRAM as local buffer. The Windows driver technology is researched to achieve the controlling of multiple cards respectively and the interruption communication between the driver and user application program. A novel strategy is employed to solve the non-linear conversion problem in data acquisition. The experimental results show that the proposed method can cut down the system error evidently and the maximum acquisition error after compensation is less than 2mV. This technology can be applied to multi-channel, high-speed and high-accuracy data acquisition in control systems.
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